diff --git a/OpenACC.make b/OpenACC.make
index 161c20e..2799603 100644
--- a/OpenACC.make
+++ b/OpenACC.make
@@ -8,7 +8,7 @@ COMPILER_PGI = pgc++
 COMPILER_CRAY = CC
 CXX = $(COMPILER_$(COMPILER))
 
-FLAGS_ = -O3
+FLAGS_ = -O3 -std=c++11
 
 FLAGS_PGI = -std=c++11 -O3 -acc
 ifeq ($(COMPILER), PGI)
diff --git a/OpenCL.make b/OpenCL.make
index ce7db6e..62c4f43 100644
--- a/OpenCL.make
+++ b/OpenCL.make
@@ -7,7 +7,7 @@ COMPILER_ = $(CXX)
 COMPILER_GNU = g++
 COMPILER_CRAY = CC
 
-FLAGS_ = -O3
+FLAGS_ = -O3 -std=c++11
 FLAGS_GNU = -O3 -std=c++11
 FLAGS_CRAY = -O3 -hstd=c++11
 CXXFLAGS=$(FLAGS_$(COMPILER))
diff --git a/OpenMP.make b/OpenMP.make
index d4b7519..2fd47e7 100644
--- a/OpenMP.make
+++ b/OpenMP.make
@@ -10,7 +10,7 @@ COMPILER_CRAY = CC
 COMPILER_CLANG = clang++
 CXX = $(COMPILER_$(COMPILER))
 
-FLAGS_ = -O3
+FLAGS_ = -O3 -std=c++11
 FLAGS_GNU = -O3 -std=c++11
 FLAGS_INTEL = -O3 -std=c++11 -xHOST
 FLAGS_CRAY = -O3 -hstd=c++11